I've been having this problem (more of an annoyance, than anything). First off, the volume knob on my Ibanez GSR200 started becoming rediculously loose, bouncing around whenever my bass jiggled. After that, the tone knob followed. I don't jump around a lot with this, being a practice bass, so I'm wondering, has anyone else had this problem (with this or any other kind of bass)? If so, what's the easiest way to correct it?